It's not cancer, or heart disease – it's suicide. It accounts for nearly 5,000 male deaths per year. And nobody really seems to be talking about it.

British rapper Stephen Manderson (better known as Professor Green) lost his dad, Peter, to suicide just seven years ago. He's undertaken a deep exploration of the topic and gone on his own personal journey to get some answers in an extremely raw documentary, Professor Green: Suicide And Me, which airs on BBC Three tonight.

"It’s not a topic anyone really wants to talk about," he says. "But I’d like to get a better understanding of why my dad did what he did. And I’d like to, bit by bit, remove the taboo that surrounds it."

What were the first steps in getting a documentary like that made?

Antidote and BBC Three approached us and we sat down with them and started to put ideas out there. It wasn't really about it being the best idea for a programme to make, it was more "This is quite close to me; this is important." I saw the response to the documentary [on suicide] I did for Radio 1, and it felt like the right thing to do.

How did you decide who you were going to speak to in the film?

With the Radio 1 documentary, I asked that a psychotherapist be present. I always wanted to understand the science behind it. I never spoke to anyone when I going through it, and as Debbie [Stephen's aunt] pointed out, there's no support readily available. You have to sort it out yourself, and most people won't. Debbie went through hell: she lost David [his dad's brother] to suicide, her sister to leukaemia a year later, and then my dad to suicide. There was no help there whatsoever.

You talk a lot in the film about men not opening up and just doing 'guy things'.

I don't even think it's just guys. I think it's life. People say, "Well, that's happened now" and that it's about looking at what's in front of you. You don't give too much time to what's in the past. But that has some bearing on you. It always does. Everything that happens affects you in some way or another.

What's the best way to help someone if they approach you and tell you they are feeling suicidal?

I'm not a psychotherapist and I don't have any qualifications in helping someone out, but I'd say just being with them as much as necessary. I think that's every friend's job. If you think something's wrong, you have to probe. If you know that something is wrong and you don't ask the question, then you're not being a very good friend.

Sometimes people do pluck up the courage to say something and they're told, "Oh come on mate, get it together." That's a problem that needs to be addressed and has to improve. That's one of the first things I did. I got so angry at my dad. I called him a coward, was punching walls and then I just started crying and felt so sorry. Imagine what a person would have to go through to get to that decision.

Why do you think you felt angry at first?

Because of the relationship. It was selfish. I was thinking about what he had done to me, again. He had taken away any opportunity for us to resolve anything. Deep down, there's still a little boy inside me that just wanted his dad. He was a sweet man, a kind man, and that's what made it all harder.

Has anyone approached you to thank you for helping them?

I got a tweet from someone yesterday. I've had people say that my lyrics have helped them through things but this is not something I expected. That's incredible.

@professorgreen You saved my life today, I listened to your interview and decided I had to stay, I will get better eventually. Thanks man

Is there anything you feel should follow on from this documentary, in terms of making discussing suicide less taboo?

Honestly, I think I need to do a bit of work personally. There's a lot of times where I disengage myself from the subject so I can just talk about it. I couldn't cry in every interview, but with this it's been really difficult. It has definitely made me much more aware of the fact that this is something I needed to do.

What's the best case scenario reaction to the documentary?

Another film. Then another one. And a campaign, then another campaign. I want growth. I would hate to see it just stop. This programme is hopefully the beginning of a conversation. I don't want that conversation to end any time soon.

_ Images: BBC/Antidote _

Professor Green: Suicide And Me airs tonight at 9pm on BBC Three

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